AbstractA method is disclosed for magnetically separating dis-coloring contaminants of low magnetic attractability from a crudekaolin clay to achieve, with lower field intensities than hitherto,brightness improvements which have previously been unattainablethrough magnetic separation processes and which are at sufficientlyhigh levels to obviate any requirement for flotation treatments, themethod comprising the steps of forming a dispersed aqueous slurryof said clay; seeding the slurry with a particulate of finelydivided ferromagnetic particles wherein at least 50% by weightof the particles are of less than 30 microns E.S.D., the par-ticulate being the product of aqueous co-precipitation of iron(III) with iron (II) salts in the presence of an excess of astrong base; and subjecting the seeded slurry to a magneticseparation by passing the slurry through a porous ferromagneticmatrix positioned in a magnetic field to remove at least partof the particulate together with the titaniferous contaminantsflocculated therewith, the purified product from the magneticseparation being: leached to remove leachable iron, includingat least part of the remnants of the seeding particulate.
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